The Analytical Chemistry Instrumentation Facility (ACIF) at the University of California Riverside is requesting funds for purchasing an LC-MS/MS system, which includes a Thermo Fisher Scientific TSQ Vantage triple-quadrupole mass spectrometer and an Agilent 1200 capillary HPLC system. The requested instrument will be installed at ACIF and managed by the ACIF staff at the University of California Riverside. In this respect, the Mass Spectrometry Facility at ACIF has served the whole Riverside campus and many investigators around the nation for more than 25 years. The requested instrument will be used primarily for supporting the ongoing research of a number of NIH-funded investigators at the University of California Riverside. Although ACIF houses several mass spectrometers and there are several other instruments in individual research faculty's labs, there is no instrument on UC Riverside campus that can meet the demanding analytical needs of the research projects associated with the proposed instrument. In particular, there is a lack of capability in quantifying accurately trace amounts of nucleic acids and their constituents isolated from complex biological matrices. In addition, true precursor-ion and neutral-loss scans are not available on any instruments that are presently available to the users. These two features are available on the proposed triple quadrupole mass spectrometer and will be very useful for the discovery of new damage products of DNA. The requested instrument will enhance substantially the capability of the participating faculty in detecting and quantifying damaged or modified nucleosides, nucleotides, and nucleic acids. PUBLIC HEALTH RELEVANCE: The proposed LC-MS/MS system will benefit the research projects of a group of NIH-funded investigators who are interested in research associated with nucleosides, nucleotides, and nucleic acids. The outcome of these research projects will improve our understanding of a number of human diseases including cancer and diabetes.